"Stephen" wrote in message
...
On Thu, 20 Aug 2009 03:43:54 -0700 (PDT), chudford
wrote:

If not why don't you turn off the mains water and drain down the HW,
this would be the safest way.

So simple, why didn't I think of that? OTOH it would mean pouring a
whole hot tank away, which does seem wasteful. I haven't looked in the
airing cupboard yet, so I hope I might find a gate valve or something
in there. I have one in ours; are they fitted routinely,. if so, that
is promising but it does mean I won't get to buy a freezing kit!

Well, you don't need to drain the hot tank, just drain the cold, the hot is
fed from the cold, at the bottom of the tank, and the take off is from the
top (heat rises!) so once the cold water tank is empty, the hot tank will
just sit there full - you will obviuslly need to drain the pipe between the
tank and your work, but as soon as that is empty, then the hot water will
just sit in the cylider.

I expect if the cylinder is hot, and you then turn off the boiler, this will
mean the water won't expand any more, so you shouldnt get any dribbling.

You may find a gate valve, usually between the cold tanks and the hot
cylinder, but you may not be able to turn it if it hasn't been used in a
long time, and even if it does "work" it may not actually shut the water
off, as they are crap!

If it were me, I would install a full bore lever valve like this if I were
draining stuff down, for the future...
http://www.screwfix.com/prods/17293

NOT one of these
http://www.screwfix.com/prods/18334

Also, where you are working under the sink, install some of these if you can
http://www.screwfix.com/prods/76597

The new taps may come with flexable tails, if so, they will probably screw
directly onto the valve.

And if you are doing all of this, make sure the mains water shut-off is
elderly relative friendly too - installing a lever valve is a hell of a lot
easer to use than a traditional stop cock

One of these is even easier (although I have not used one myself yet, I have
had good feedback from someone who has one)
http://www.surestop.co.uk/


Toby...